Sorry to hear that Marcus… so here are a few questions for you…
1. Does the live demo site function in mobile view (or size) http://demo.styledthemes.com/encounters/
2. Did you make any changes at the same time or after you updated the theme?
3. What browser are you using and version?
4. What kind of changes did you make to the menu (if any)?
The menu styling was changed in the new version so perhaps your child theme override of CSS for the menu might not be valid anymore…or partially.